分类目录归档:Oracle备份恢复

RBA和实例恢复关系

1.关于heartbeat和checkpoint
在这次的删除过程中我没有执行commit,而是直接abort数据库。整个删除过程执行了近6分钟,控制文件的心跳每三秒进行一次,心跳是把low cache rba记录到了控制文件中,而没有真正的把全部的脏数据写入到磁盘( 只有发生了checkpoint时候,才会把相关的脏数据写入到磁盘,而这里的控制文件的heartbeat和checkpoint是两回事,checkpoint一般是在切换日志,数据文件正常离线,执行begin backup命令时发生,昨晚晚上后面的一个困惑就是上面的英文描述,让我把这两者搞混淆了)

2.三种rba解释
low rba :在buffer cache中的数据块第一次数据改变所对应的RAB。
high rba :在buffer cache中的数据块最近一次数据改变时所对应的RAB。
on-disk rba:是 lgwr 写日志文件的最末位置的地址。

3.实例恢复过程解释
实例恢复的时候,是从控制文件heartbeat记录的low rba开始读redo log数据(会多读取一点,因为heartbeat是每三秒执行一次,假设在2.9秒的时候,数据库异常down了,控制文件中记录的还是2.9秒前的low rba,这个时候,从该点开始读取redo),恢复到on-disk rba,而不是high rba(high rba一般情况下会大于on-disk rba,但是因为high rba比on-disk rba多的部分记录在redo log buffer中,在实例恢复的时候,因为其未被记录到redo log file中,所以不能被恢复,其实也没有必要恢复,因为该数据肯定是没有commit或者rollback)

具体内容和实验请见:RBA和实例恢复关系

发表在 Oracle备份恢复 | 评论关闭

ORA-600 kcratr_nab_less_than_odr故障解决

朋友的数据库服务器出现ORA-00600[kcratr_nab_less_than_odr],不能open数据库
1.open数据库报ORA-00600[kcratr_nab_less_than_odr]

SQL> ALTER DATABASE OPEN;
ALTER DATABASE OPEN
*
第 1 行出现错误:
ORA-00600: 内部错误代码, 参数: [kcratr_nab_less_than_odr], [1], [99189],
[43531], [43569], [], [], [], [], [], [], []

2.查看alert日志

Wed Jan 11 13:56:16 2012
ALTER DATABASE OPEN
Beginning crash recovery of 1 threads
 parallel recovery started with 2 processes
Started redo scan
Completed redo scan
 read 54591 KB redo, 0 data blocks need recovery
Errors in file d:\dbdms\diag\rdbms\dbdms\dbdms\trace\dbdms_ora_3108.trc  (incident=818557):
ORA-00600: 内部错误代码, 参数: [kcratr_nab_less_than_odr], [1], [99189], [43531], [43569], [], [], [], [], [], [], []
Incident details in: d:\dbdms\diag\rdbms\dbdms\dbdms\incident\incdir_818557\dbdms_ora_3936_i818557.trc
Aborting crash recovery due to error 600
Errors in file d:\dbdms\diag\rdbms\dbdms\dbdms\trace\dbdms_ora_3108.trc:
ORA-00600: 内部错误代码, 参数: [kcratr_nab_less_than_odr], [1], [99189], [43531], [43569], [], [], [], [], [], [], []
Errors in file d:\dbdms\diag\rdbms\dbdms\dbdms\trace\dbdms_ora_3108.trc:
ORA-00600: 内部错误代码, 参数: [kcratr_nab_less_than_odr], [1], [99189], [43531], [43569], [], [], [], [], [], [], []
ORA-600 signalled during: ALTER DATABASE OPEN...
Trace dumping is performing id=[cdmp_20120110214555]

3.查看trace文件

Trace file d:\dbdms\diag\rdbms\dbdms\dbdms\trace\dbdms_ora_3108.trc
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
Windows NT Version V6.1 Service Pack 1 
CPU                 : 2 - type 8664, 2 Physical Cores
Process Affinity    : 0x0x0000000000000000
Memory (Avail/Total): Ph:2250M/4060M, Ph+PgF:5868M/8119M 
Instance name: dbdms
Redo thread mounted by this instance: 1
Oracle process number: 17
Windows thread id: 3108, image: ORACLE.EXE (SHAD)
…………………………
WARNING! Crash recovery of thread 1 seq 99189 is
ending at redo block 43531 but should not have ended before
redo block 43569
Incident 826550 created, dump file: d:\dbdms\diag\rdbms\dbdms\dbdms\incident\incdir_826550\dbdms_ora_3108_i826550.trc
ORA-00600: ??????, ??: [kcratr_nab_less_than_odr], [1], [99189], [43531], [43569], [], [], [], [], [], [], []

ORA-00600: ??????, ??: [kcratr_nab_less_than_odr], [1], [99189], [43531], [43569], [], [], [], [], [], [], []
ORA-00600: ??????, ??: [kcratr_nab_less_than_odr], [1], [99189], [43531], [43569], [], [], [], [], [], [], []

通过alert和trace中的内容可以知道,数据库需要恢复到rba到43569,但是因为某种原因实例恢复的时候,只能利用1 thread 99189 seq#,恢复rba到43531。从而导致数据库无法正常open

This Problem is caused by Storage Problem of the Database Files. 
The Subsystem (eg. SAN) crashed while the Database was open. 
The Database then crashed since the Database Files were not accessible anymore. 
This caused a lost Write into the Online RedoLogs and so Instance Recovery is not possible and raising the ORA-600.

4.解决方法

SQL> SELECT STATUS FROM V$INSTANCE;

STATUS
------------
MOUNTED

--尝试直接recover database
SQL> RECOVER DATABASE ;
ORA-00283: 恢复会话因错误而取消
ORA-00264: 不要求恢复
--提示不用恢复

--再打开数据库,还是kcratr_nab_less_than_odr错误警告
SQL> ALTER DATABASE OPEN;
ALTER DATABASE OPEN
*
第 1 行出现错误:
ORA-00600: 内部错误代码, 参数: [kcratr_nab_less_than_odr], [1], [99189],
[43531], [43569], [], [], [], [], [], [], []

--尝试不完全恢复
SQL> RECOVER DATABASE UNTIL CANCEL;
ORA-10879: error signaled in parallel recovery slave
ORA-01547: 警告: RECOVER 成功但 OPEN RESETLOGS 将出现如下错误
ORA-01152: 文件 1 没有从过旧的备份中还原
ORA-01110: 数据文件 1: 'D:\DBDMS\DATA\SYSTEM01.DBF'

--重建控制文件
SQL> ALTER DATABASE BACKUP CONTROLFILE TO TRACE AS 'D:/1.TXT';

数据库已更改。

SQL> SHUTDOWN IMMEDIATE;
ORA-01109: 数据库未打开


已经卸载数据库。
ORACLE 例程已经关闭。
SQL> STARTUP NOMOUNT;
ORACLE 例程已经启动。

Total System Global Area  417546240 bytes
Fixed Size                  2176328 bytes
Variable Size             268438200 bytes
Database Buffers          138412032 bytes
Redo Buffers                8519680 bytes
SQL> CREATE CONTROLFILE REUSE DATABASE "DBDMS" NORESETLOGS  NOARCHIVELOG
  2      MAXLOGFILES 16
  3      MAXLOGMEMBERS 3
  4      MAXDATAFILES 100
  5      MAXINSTANCES 8
  6      MAXLOGHISTORY 18688
  7  LOGFILE
  8    GROUP 1 'D:\DBDMS\LOG\REDO01.LOG'  SIZE 50M BLOCKSIZE 512,
  9    GROUP 2 'D:\DBDMS\LOG\REDO02.LOG'  SIZE 50M BLOCKSIZE 512,
 10    GROUP 3 'D:\DBDMS\LOG\REDO03.LOG'  SIZE 50M BLOCKSIZE 512
 11  DATAFILE
 12    'D:\DBDMS\DATA\SYSTEM01.DBF',
 13    'D:\DBDMS\DATA\SYSAUX01.DBF',
 14    'D:\DBDMS\DATA\RBSG01.DBF',
 15    'D:\DBDMS\DATA\DATA01.DBF',
 16    'D:\DBDMS\DATA\INDX01.DBF',
 17    'D:\DBDMS\DATA\DATA02.DBF',
 18    'D:\DBDMS\DATA\DATA03.DBF',
 19    'D:\DBDMS\DATA\DATA04.DBF',
 20    'D:\DBDMS\DATA\INDX02.DBF',
 21    'D:\DBDMS\DATA\SYSTEM02.DBF'
 22  CHARACTER SET ZHS16GBK
 23  ;

控制文件已创建。

--继续尝试恢复
SQL> RECOVER DATABASE ;
完成介质恢复。
SQL> ALTER DATABASE OPEN;

数据库已更改。
--open成功

在这次恢复中,主要就是重建控制文件,然后直接恢复成功,如果redo有损坏,那么可能需要使用不完全恢复,然后使用resetlogs打开数据库

发表在 ORA-xxxxx, Oracle备份恢复 | 标签为 , , | 7 条评论

恢复被rm意外删除数据文件

一.模拟数据文件删除

[oracle@node1 ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.3.0 Production on Sat Dec 31 22:00:52 2011

Copyright (c) 1982, 2011, Oracle.  All rights reserved.

--数据库版本
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options

--所有数据文件
SQL> select name from v$datafile;

NAME
--------------------------------------------------------------------------------
/opt/oracle/oradata/ora11g/system01.dbf
/opt/oracle/oradata/ora11g/sysaux01.dbf
/opt/oracle/oradata/ora11g/undotbs01.dbf
/opt/oracle/oradata/ora11g/users01.dbf
/opt/oracle/oradata/ora11g/example01.dbf

--删除example01.dbf数据文件
SQL> !rm /opt/oracle/oradata/ora11g/example01.dbf

SQL> !ls -l /opt/oracle/oradata/ora11g/example01.dbf
ls: /opt/oracle/oradata/ora11g/example01.dbf: 没有那个文件或目录

--因为数据文件被删除,创建表失败
SQL> create table t_xifenfei tablespace example
  2  as select * from dba_tables;
as select * from dba_tables
                 *
ERROR at line 2:
ORA-01116: error in opening database file 5
ORA-01110: data file 5: '/opt/oracle/oradata/ora11g/example01.dbf'
ORA-27041: unable to open file
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3

二.找回数据文件

--查找dbw进程spid
[oracle@node1 ~]$ ps -ef|grep dbw|grep -v grep
oracle   18387     1  0 Dec22 ?        00:00:12 ora_dbw0_ora11g

--查看该进程所有文件句柄
[oracle@node1 ~]$ ll /proc/18387/fd
总计 0
lr-x------ 1 oracle oinstall 64 12-31 22:03 0 -> /dev/null
l-wx------ 1 oracle oinstall 64 12-31 22:03 1 -> /dev/null
lr-x------ 1 oracle oinstall 64 12-31 22:03 10 -> /dev/zero
lr-x------ 1 oracle oinstall 64 12-31 22:03 11 -> /dev/zero
lr-x------ 1 oracle oinstall 64 12-31 22:03 12 -> /opt/oracle/product/11.2.0/db_1/rdbms/mesg/orazhs.msb
lrwx------ 1 oracle oinstall 64 12-31 22:03 13 -> /opt/oracle/product/11.2.0/db_1/dbs/hc_ora11g.dat
lr-x------ 1 oracle oinstall 64 12-31 22:03 14 -> /proc/18387/fd
lr-x------ 1 oracle oinstall 64 12-31 22:03 15 -> /dev/zero
lr-x------ 1 oracle oinstall 64 12-31 22:03 16 -> /opt/oracle/product/11.2.0/db_1/rdbms/mesg/oraus.msb
lrwx------ 1 oracle oinstall 64 12-31 22:03 17 -> /opt/oracle/product/11.2.0/db_1/dbs/hc_ora11g.dat
lrwx------ 1 oracle oinstall 64 12-31 22:03 18 -> /opt/oracle/product/11.2.0/db_1/dbs/lkORA11G
lr-x------ 1 oracle oinstall 64 12-31 22:03 19 -> /opt/oracle/product/11.2.0/db_1/rdbms/mesg/orazhs.msb
l-wx------ 1 oracle oinstall 64 12-31 22:03 2 -> /dev/null
lr-x------ 1 oracle oinstall 64 12-31 22:03 20 -> /opt/oracle/product/11.2.0/db_1/rdbms/mesg/oraus.msb
lrwx------ 1 oracle oinstall 64 12-31 22:03 21 -> socket:[441562]
lrwx------ 1 oracle oinstall 64 12-31 22:03 256 -> /opt/oracle/oradata/ora11g/control01.ctl
lrwx------ 1 oracle oinstall 64 12-31 22:03 257 -> /opt/oracle/oradata/ora11g/system01.dbf
lrwx------ 1 oracle oinstall 64 12-31 22:03 258 -> /opt/oracle/oradata/ora11g/sysaux01.dbf
lrwx------ 1 oracle oinstall 64 12-31 22:03 259 -> /opt/oracle/oradata/ora11g/undotbs01.dbf
lrwx------ 1 oracle oinstall 64 12-31 22:03 260 -> /opt/oracle/oradata/ora11g/users01.dbf
lrwx------ 1 oracle oinstall 64 12-31 22:03 261 -> /opt/oracle/oradata/ora11g/example01.dbf (deleted)
lrwx------ 1 oracle oinstall 64 12-31 22:03 262 -> /opt/oracle/oradata/ora11g/temp01.dbf
lr-x------ 1 oracle oinstall 64 12-31 22:03 3 -> /dev/null
lr-x------ 1 oracle oinstall 64 12-31 22:03 4 -> /dev/null
lrwx------ 1 oracle oinstall 64 12-31 22:03 5 -> /opt/oracle/product/11.2.0/db_1/dbs/hc_ora11g.dat
lr-x------ 1 oracle oinstall 64 12-31 22:03 6 -> /dev/null
lr-x------ 1 oracle oinstall 64 12-31 22:03 7 -> /dev/null
lr-x------ 1 oracle oinstall 64 12-31 22:03 8 -> /dev/null
lr-x------ 1 oracle oinstall 64 12-31 22:03 9 -> /dev/null
--通过句柄恢复数据文件[被删除数据文件会被标示(deleted)]
[oracle@node1 ~]$ cp /proc/18387/fd/261 /opt/oracle/oradata/ora11g/example01.dbf
--确认该数据文件已经恢复成功
[oracle@node1 ~]$ ll /opt/oracle/oradata/ora11g/example01.dbf
-rw-r----- 1 oracle oinstall 362422272 12-31 22:05 /opt/oracle/oradata/ora11g/example01.dbf

三.数据文件online

SQL> alter database datafile 5 offline;
 
Database altered.
 
SQL> recover datafile 5;
Media recovery complete.
SQL> alter database datafile 5 online;
 
Database altered.

SQL> create table t_xifenfei tablespace example
  2  as select * from dba_tables;

Table created.

四.补充说明
在意外使用os命令删除掉数据文件时,千万不要慌张重启数据库或者操作系统,可以通过dbwn进程相关句柄找回数据文件

发表在 Linux, Oracle备份恢复 | 7 条评论